The Jewish position on this, is that the long life of ancient people in the OT were the product of living a near-sinless life.
Since old Hebrew Judaism has no afterlife, the personal reward for following God's law, was life extension.
 Now these are the commandments, the statutes, and the judgments, which the LORD your God commanded to teach you, that ye might do them in the land whither ye go to possess it:
 That thou mightest fear the LORD thy God, to keep all his statutes and his commandments, which I command thee, thou, and thy son, and thy son's son, all the days of thy life; and that thy days may be prolonged.
The book of Job states fairly clearly (in a circular and confused way), that the product of displeasing God, is personal pestilence. Although it's not terribly clear what Job did, to piss off God, because it's circular, all his friends come to him and tell him that he must have done something, because bad things don't happen to good people. Job 21 states Job's sudden observation that wicked people all seem to do pretty well, and it must be God giving them fringe benefits.
Matt 9 also equates sin with disease
 And, behold, they brought to him a man sick of the palsy, lying on a bed: and Jesus seeing their faith said unto the sick of the palsy; Son, be of good cheer; thy sins be forgiven thee.
 And, behold, certain of the scribes said within themselves, This man blasphemeth.
 And Jesus knowing their thoughts said, Wherefore think ye evil in your hearts?
 For whether is easier, to say, Thy sins be forgiven thee; or to say, Arise, and walk?
The Pharisee Hillel, who was regarded as great, was reputed to have lived for 100 years.
Therefore it's compulsory for the Hebrew texts to have mythical people in them, who lived a long time. This way, priests can say that everybody contemporary is a sinner, and they all have to try much harder, and give more money to the temple, if they want to live as long as Noah, or Job. However, there is an exceedingly poor correlation with righteousness and longevity. To cope with this problem, they then had to invent other reasons why people were getting sick, such as God testing people. It didn't work very well.